IBM PC compatible multi-chip module

ABSTRACT

A multi-chip module and a chip set that comprises a plurality of the multi-chip modules. The multi-chip module includes a plurality of functional circuits provided on a substrate, the circuits defining a plurality of signal inputs and outputs. A plurality of pins are secured in a single row along the periphery of the substrate and are connected to the inputs and outputs. The pins include a set of 91 signal pins, two ground pins, and a power pin, the signal pins having a configuration complying in number and signal type with the IEEE-Prequirements to define an ISA bus. The multi-hip module includes a rectangular housing wherein the pins, in the form of gull wing pins, extend laterally from a peripherally extending wall. The ISA bus pins extend along one side and partially along adjacent sides of the rectangular module. The functional circuits of one embodiment of the module include a CPU, serial interfaces, a parallel interface, a hard drive interface, a floppy disk interface, a keyboard interface, and flash memory. Other multi-chip modules can include a PCMCIA interface, an Ethernet interface, or a display controller.

CROSS REFERENCE TO RELATED APPLICATIONS

This is a continuation of Ser. No. 08/757,896, filed Nov. 27, 1996, which is a continuation-in-part of Ser. No. 08/564,688, filed Nov. 29, 1995, now U.S. Pat. No. 5,742,844.

FIELD OF THE INVENTION

This invention relates to a multi-chip module.

BACKGROUND OF THE INVENTION

The most successful applications of computer technology have been those that people do not see. Microcontrollers and microprocessors govern automotive anti lock braking systems, automatic teller machines, elevators, subway ticket systems, and medical equipment. These hidden computers, otherwise known as embedded systems, permeate our lives. The embedded control market is, in fact, growing significantly faster than the desk top computing market. A major trend is the move from 4- and 8-bit processors to more powerful devices that provide more computing power and enable more “friendly” man-machine interfaces. A study by Desk Top Strategies showed that in 1994 over 320 million 16- and 32-bit embedded control processors were shipped to original equipment manufacturers (OEMs) for use in embedded control applications. In contrast, only 50 million were shipped to desk top computer manufacturers. The compound annual growth rate for 32-bit processors in the embedded market from 1992 to 1997 is projected to be 53 percent, compared with an estimated 32 percent in the desk top market.

The area of greatest growth in the embedded control market is the segment of ultra-miniature controllers for portable and transportable instruments. OEMs have indicated a strong interest in developing products with the PC architecture, but have found that size, integration, power, reliability, or cost constraints make existing broad-level products unsuitable for their applications.

The Cardio 386 developed by S-Mos Systems comprises a full function, small footprint, X86 computer that includes a CPU, all standard PC-type I/O controllers, PGA graphics, floppy and hard disk drive interfaces, DRAM, flash memory, and transparent power management. It adopts a PC AT architecture which complies with the ISA (industry standard architecture) bus pin configuration. However, it makes use of a unique edge connector comprising a plurality of tracks formed into rows on a card. This is received in a complementary slot for connection to peripheral devices. The use of a connector for connecting the module to a board makes its implementation inherently unreliable since vibrations can compromise the electrical connections between the various tracks forming the pins, and the corresponding contacts of the slot connector. Furthermore, no provision is made for integrating the module with proprietary hardware of OEMs (original equipment manufacturers).

Another prior art device is the Northstar III by Micro Module Systems that comprises a multi-chip module, including a Pentium processor, a cache controller, and RAM incorporated in a 349 pin PGA package. Once again, no facility is provided for interfacing with OEM proprietary hardware, Furthermore, the North Star module is packaged in a 349 pin PGA which makes simple direct connection to peripheral devices impossible without complicated track layout design. Therefore it does not allow the module to be simply dropped into an OEM system.

OBJECTS AND SUMMARY OF THE INVENTION

It is an object of the invention to incorporate a multi-chip module in an ultra-miniature form factor. In particular it is an object of the invention to provide a module the size of a large integrated circuit.

It is a further object of the invention to provide an Intel X86 compatible computer module and peripheral controller modules wherein the computer module includes a CPU, I/O (a parallel port and two serial ports), a keyboard interface, a DRAM interface, floppy disk controller, hard disk controller, and flash disk functions based on Intel X86 architecture. Specifically, it is an object of the invention to provide a multi-chip module that provides an OEM (Original Equipment Manufacturer) with the facility for incorporating a feature set that is compatible with IBM PC/AT hardware, software, and bus pin configuration.

It is a further object of the invention to provide a module having low power consumption, broad thermal adaptability, low cost, and high reliability by eliminating cables and mounting hardware.

It is yet a further object of the invention to provide a module family having identical ISA bus pin configurations to facilitate easy interconnection.

It is yet a further object of the invention to provide a development board to form a platform for receiving a multi-chip module of the invention, thereby to provide for the quick development of pilot projects.

According to the invention there is provided a multi-chip module comprising a plurality of functional circuits provided on a substrate, the circuits defining a plurality of signal inputs and outputs, and a plurality of module pins secured in a single row along the periphery of the substrate and connected to the inputs and outputs, the module pins including a set of 91 pins, two ground pins, and a power pin, defining an ISA bus means, the signal pins having a configuration complying in number and signal type with the signal pins laid down under the IEEE-P996 specification, and as applied in the ISA (Industry Standard Architecture) requirements. For this reason it will hereinafter be referred as to as the ISA bus.

The module can be rectangular in shape, having a first side, a second side opposite the first side, a third side, and a fourth side, and is defined by an upper surface, a lower surface, and a peripheral wall, and wherein the plurality of pins extend from the peripheral wall.

The pins of the ISA bus means of the present invention preferably comprise: pin 38 corresponding to signal IOCHCK; pin 39 corresponding to signal SD07; pin 40 corresponding to signal RESETDRV; pin 41 corresponding signal SD06; pin 42 corresponding to signal SD05; pin 43 corresponding to signal IRQ9; pin 44 corresponding to signal SD04; pin 45 corresponding to signal SD03; pin 46 corresponding to signal DRQ2; pin 47 corresponding to signal DRQ20UT-; pin 48 corresponding to signal SD02; pin 49 corresponding to signal SD01-; pin 50 corresponding to signal 0WS; pin 51 corresponding to signal SD00; pin 52 corresponding to signal IOCHRDY; pin 53 corresponding to signal SBHE-; pin 54 corresponding to signal MEMSC16-; pin 55 corresponding to signal AEN; pin 56 corresponding to signal SMEMW-; pin 57 corresponding to signal LA23; pin 58 corresponding to signal IOCS 16-; pin 59 corresponding to signal SA19; pin 60 corresponding to signal SMEMR-; pin 61 corresponding to signal LA22; pin 62 corresponding to signal IRQI0; pin 63 corresponding to signal SA18; pin 64 corresponding to signal IOW-; pin 65 corresponding to signal LA21; pin 66 corresponding to signal IRQ11; pin 67 corresponding to GND; pin 68 corresponding to signal SA17; pin 69 corresponding to signal IOR-; pin 70 corresponding to signal LA20; pin 71 corresponding to signal IRQ12; pin 72 corresponding to signal SA16; pin 73 corresponding to signal DACK3-; pin 74 corresponding to signal LA19; pin 75 corresponding to signal IRQ15; pin 76 corresponding to signal SA15; pin 77 corresponding to signal DRQ3; pin 78 corresponding to signal LA18; pin 79 corresponding to signal IRQ14; pin 80 corresponding to signal SA14; pin 81 corresponding to signal DACK1-; pin 82 corresponding to signal LA17; pin 83 corresponding to signal DACK0-; pin 84 corresponding to signal SA13; pin 85 corresponding to VCC; pin 86 corresponding to signal DRQ1-; pin 87 corresponding to signal MEMR-; pin 88 corresponding to signal DRQ0; pin 89 corresponding to signal SA12; pin 90 corresponding to signal REFRESH-; pin 91 corresponding to signal MEMW-; pin 92 corresponding to signal DACK5-; pin 93 corresponding to signal SA11; pin 94 corresponding to signal SYSCLK; pin 95 conresponding to signal SD08; pin 96 corresponding to signal DRQS; pin 97 corresponding to signal SA10; pin 98 corresponding to signal IRQ7; pin 99 corresponding to signal IRQ7OUT; pin 100 corresponding to signal SD09; pin 101 corresponding to signal DACK6-; pin 102 corresponding to GND; pin 103 corresponding to signal SA09; pin 104 corresponiding to signal IRQ6; pin 105 corresponding to signal IRQ6OUT; pin 106 corresponding to signal SD10; pin 107 corresponding to signal DRQ6; pin 108 corresponding to signal SA08; pin 109 corresponding to signal IRQ5; pin 110 corresponding to signal SD11; pin 111 corresponding to signal DACK7-; pin 112 corresponding to signal SA07; pin 113 corresponding to signal IRQ4; pin 114 corresponding to signal SD12; pin 115 corresponding to signal DRQ7; pin 116 corresponding to signal SA06; pin 117 corresponding to signal IRQ3; pin 118 corresponding to signal SD13; pin 119 corresponding to signal SA05; pin 120 corresponding to signal DACK2-; pin 121 corresponding to signal SD14; pin 122 corresponding to signal MASTER-; pin 123 corresponding to signal SA04; pin 124 corresponding to signal TC; pin 125 corresponding to signal SD15; pin 126 corresponding to signal SA03; pin 127 corresponding to signal BALE; pin 128 corresponding to signal SA02; pin 129 corresponding to signal SA01; pin 130 corresponding to signal OSC; and pin 131 corresponding to signal SA00.

The pin of the ISA bus means of the present invention can alternatively comprise: pin 38 corresponding to signal SA00; pin 39 corresponding to signal OSC; pin 40 corresponding to signal SA01; pin 41 corresponding signal SA02; pin 42 corresponding to signal BALE; pin 43 corresponding to signal SA03; pin 44 corresponding to signal SD15; pin 45 corresponding to signal TC; pin 46 corresponding to signal SA04; pin 47 corresponding to signal MASTER-; pin 48 corresponding to signal SD14; pin 49 corresponding to signal DACK2-; pin 50 corresponding to signal SA05; pin 51 corresponding to signal SD13; pin 52 corresponding to signal IRQ3; pin 53 corresponding to signal SA06; pin 54 corresponding to signal DRQ7; pin 55 corresponding to signal SD12; pin 56 corresponding to signal IRQ4; pin 57 corresponding to signal SA07; pin 58 corresponding to signal DACK7-; pin 59 corresponding to signal SD11; pin 60 corresponding to signal IRQ5; pin 61 corresponding to signal SA08; pin 62 corresponding to signal DRQ6; pin 63 corresponding to signal SD10; pin 64 corresponding to signal IRQ60UT; pin 65 corresponding to signal IRQ6; pin 66 corresponding to signal SA09; pin 67 corresponding to GND; pin 68 corresponding to signal DACK6-; pin 69 corresponding to signal SD09; pin 70 corresponding to signal IRQ70UT; pin 71 corresponding to signal IRQ7; pin 72 corresponding to signal SA10; pin 73 corresponding to signal DRQ5; pin 74 corresponding to signal SD08; pin 75 corresponding to signal SYSCLK; pin 76 corresponding to signal SA11; pin 77 corresponding to signal DACK5-; pin 78 corresponding to signal MEMW-; pin 79 corresponding to signal REFRESH-; pin 80 corresponding to signal SA12; pin 81 corresponding to signal DRQ5; pin 82 corresponding to signal MEMR-; pin 83 corresponding to signal DRQ1; pin 84 corresponding to signal SA13; pin 85 corresponding to VCC; pin 86 corresponding to signal DACKO-; pin 87 corresponding to signal LA17; pin 88 corresponding to signal DACK1-; pin 89 corresponding to signal SA14; pin 90 corresponding to signal IRQ14; pin 91 corresponding to signal LA18; pin 92 corresponding to signal DRQ3; pin 93 corresponding to signal SA15; pin 94 corresponding to signal IRQ15; pin 95 corresponding to signal LA19; pin 96 corresponding to signal DACK3-; pin 97 corresponding to signal SA16; pin 98 corresponding to signal IRQ12; pin 99 corresponding to signal LA20; pin 100 corresponding to signal IOR-; pin 101 corresponding to signal SA17; pin 102 corresponding to GND; pin 103 corresponding to signal IRQ11; pin 104 corresponding to signal LA21; pin 105 corresponding to signal IOW-; pin 106 corresponding to signal SA18; pin 107 corresponding to signal IRQ10; pin 108 corresponding to signal LA22; pin 109 corresponding to signal SMEMR-; pin 110 corresponding to signal SA19; pin 111 corresponding to signal IOCS16-; pin 112 corresponding to signal LA23; pin 113 corresponding to signal SMEMW-; pin 114 corresponding to signal AEN; pin 115 corresponding to signal MEMCS 16-; pin 116 corresponding to signal SBHE-; pin 117 corresponding to signal IOCHRDY; pin 118 corresponding to signal SD00; pin 119 corresponding to signal 0WS-; pin 120 corresponding to signal SD00; pin 121 corresponding to signal SD02; pin 122 corresponding to signal DRQ2OUT; pin 123 corresponding to signal DRQ2; pin 124 corresponding to signal SD03; pin 125 corresponding to signal SD04; pin 126 corresponding to signal IRQ9; pin 127 corresponding to signal SD05; pin 128 corresponding to signal SD06; pin 129 corresponding to signal RESETDRV; pin 130 corresponding to signal SD07; and pin 131 corresponding to signal IOCHCK-.The ISA bus pins preferably extend along the first side and at least partially along the third and fourth sides. The multi-chip module can include 240 module pins.

The functional circuits in a module can include a central processing unit. The functional circuits can further include two serial interfaces, a parallel interface, a hard drive interface, a floppy disk interface, a keyboard interface, and flash memory.

Other modules can include functional circuits that include a PCMCIA interface, an Ethernet interface, or a display controller.

The substrate can comprise a printed circuit board and the functional circuits comprise semiconductor devices which can be packaged or can be in bare die form secured to the printed circuit board.

Further, according to the invention, there is provided a multi-chip module comprising a plurality of functional circuits encapsulated in a rectangular housing, the housing having an upper surface and a lower surface, and a peripheral wall extending along a first side, a second side opposite the first side, a third side, and a fourth side; and a plurality of pins extending laterally from the peripheral wall, wherein the pins include a set of 91 signal pins, two ground pins and a power pin defining an ISA bus means, the signal pins of which comply in number and signal type, with the signal pins laid down under the IEEE-P996, and as applied in the ISA (Industry Standard Architecture) requirements.

Still further, according to the invention, there is provided a module family comprising a plurality of functionally different modules, wherein each module has a plurality of pins and the pins of each module include a set of 91 signal pins, two ground pins, and a power pin, defining an ISA bus means, the signal pins of which comply in number and signal type with the signal pins laid down under the IEEE-P996, and as applied in the ISA (Industry Standard Architecture) requirements.

Each module can comprise at least one functional circuit encapsulated in a rectangular housing, the housing having an upper surface and a lower surface, and a peripheral wall extending along a first side, a second side opposite the first side, a third side, and a fourth side, and wherein the pins of the module extend laterally from the peripheral wall.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of a multi-chip module of the invention;

FIG. 2 is a side view of the module of FIG. 1;

FIG. 3 is a block diagram of a multi-chip module of the invention;

FIG. 4 is a schematic representation of the first embodiment of a multi-chip module of the invention indicating the configuration of the pins;

FIG. 5 is a schematic representation of the alternative embodiment of a multi-chip module of the invention indicating the configuration of the pins;

FIG. 6 shows a PC board layout for a development board showing the mounting site for the module of FIG. 1, and

FIG. 7 is a schematic representation of a number of different modules in accordance with the invention connected to each other by means of their ISA buses to form a module family of the invention.

DESCRIPTION OF PREFERRED EMBODIMENTS

A need exists in the field of embedded applications for small, highly reliable computer systems that draw little power, are easy to integrate, have broad thermal adaptability and are relatively inexpensive. Applications for such devices include medical instruments, data logging devices, security systems, test equipment, point-of-sale terminals, communications devices, such as Internet and facsimile machines, and navigational instruments. OEMs (original equipment manufacturers) typically use the Intel X86 architecture since it offers the world's largest body of hardware and software. The present invention has accordingly been developed to address the problems in the prior art by providing a multi-chip module packaged to resemble a large integrated circuit chip comprising a 240 pin QFP having an overall footprint of 59.54×79.88 mm. The module includes a set of pins constituting a bus for connection to the OEM designer's proprietary internal hardware. The invention specifically contemplates providing this bus with a configuration complying with the ISA (Industry Standard Architecture) requirements. This will allow the OEM designer quickly to incorporate IBM PC/AT hardware and software and to implement the module in ISA compatible proprietary product designs. The module is now described in greater detail with reference to FIGS. 1 and 2 which show a plan view and a side view, respectively, of the module.

The module 10 is a 240 pin QFP with gull wing pins having a 0.762 mm. pitch. The body is rectangular, the one side of which measures 76.2 mm and the overall footprint in this embodiment being 59.54×79.88 mm. The pins themselves are typically 0.5 mm wide, and the dimensions of distances 12 and 14 in FIG. 1 are 3.5 mm for this embodiment. By using a chip-like package in which the pins are formed around the periphery of the module 10 in a single row as illustrated in FIGS. 1 and 2, the module 10 can easily be soldered into place to form a very sturdy, reliable set of connections. Furthermore, tracks can be designed to lead directly from the pins to another device by making use of PC board tracks on one or both surfaces of the PC board without the need for several layers to route the various tracks. Since the pins are soldered directly to the interconnecting tracks, the system has inherent reliability in that it eliminates cables and mounting hardware that could otherwise vibrate loose. As many as half a dozen interconnecting cables, assorted connectors and mounting hardware required with many existing prior art single board computers, are thereby eliminated.

The module thus provides an Intel X86 compatible computer in an ultra-miniature form factor that can be integrated as easily as a semiconductor device and provides the full functionality of a desk top computer. As is described in greater detail below, the same concepts of using a chip-like module using a QFP package with gull wing pins and having an ISA compatible bus is extended also to peripheral controller modules.

By integrating a full X86 AT-compatible computer onto a proprietary OEM design, the need for multiple boards is eliminated, thereby eliminating cables and mounting hardware.

The full compatibility with PC-AT ISA allows for easy integration with low-cost hardware peripherals. The ISA, compliant bus makes it easy to interface with proprietary hardware design.

One embodiment of the module 10, having a CPU as one of its functional circuits, is illustrated in FIG. 3 and includes the standard I/O interfaces, serial ports, a parallel port, and floppy and hard disk interfaces allowing standard hardware, cables, and software libraries to be incorporated in the design. The module 10 includes an 80386 SX CPU 20 which is connected to a DRAM bus 22 and an ISA bus 24 by means of core logic 26. The core logic controls AT-compatible DMA controllers, interrupt controllers, and timers/counters. It also controls the AT keyboard controller 28 and the real time clock 30. Two serial ports 32, 34 and a parallel port 36 are provided, as are a floppy disk controller 40 and an IDE hard drive interface 42. In order to facilitate total solid state operation, internal flash memory 44 is provided that is controlled by a solid state flash disk controller 46. Power is controlled by means of a power monitor 48 that provides a power saving function by controlling CPU sleep modes, and by a watch dog timer 50. The watch dog timer 50 monitors CPU cycles to detect interrupts in the cycle thereby allowing the system to be automatically reset after a predetermined time delay.

The microprocessor and various controllers and interfaces comprise chips, optionally in die form, mounted on a multi-layer PC board, e.g. ten-layers. The CPU 20 can be a standard 33 MHz 80386 SX CPU having a DRAM controller for supporting up to 16 M bytes of DRAM. Alternatively, CPU20 can be another standard microprocessor chip such as another type of 80386 chip or die, a 80486 chip or die, a Pentium chip or die, or any other desired microprocessor which is capable of providing the function of the 80386 device.

The standard DRAM interface provides all the signals for connecting standard page-mode DRAMs of various configurations, including standard 8- and 9-bit 30-pin SIMM modules and discrete components, such as standard 1M×4 and 4M×4 DRAM chips. The interface is designed to support 70 ns or faster DRAMs. The DRAM interface consists of.

Multiplexed addresses  MA00-MA10 Bi-directional data D0-D15 Column Address Strobes CASL0- to CASL3- (low byte) CASH0- to CASH3- (high byte) Row Address Strobes RAS0- to RAS3- Memory Write Strobe DRWE-

The serial ports 32, 34 are PC-compatible asynchronous serial ports, typically treated as COM 1 and COM 2 devices by DOS.

Serial Port Resources Serial Typical I/O Standard Port Usage Address Interrupt Serial 1 COM1 3F8-3FF IRQ4 Serial 2 COM2 2F8-2FF IRQ3

Either or both serial ports can be disabled using SETUP. When disabled, the port*s I/O address and interrupt are made available for other expansion devices on the PC bus.

A full complement of input and output handshaking lines are supported by the serial ports, and all serial port signals are at standard LSTTL levels. In another embodiment, RS232C signal compatibility can be achieved by including a TTL-RS232C level converter to provide the necessary bipolar signal levels. The parallel port is a fully-compatible PC/AT parallel port providing bidirectional operation. It is typically used to support a line printer. As appears from the table below:

Parallel Port Resources Parallel Typical I/O Standard Port Usage Address Interrupt Parallel 1 LPF1 378H-37FH IRQ7

4.7K-ohm pull-ups (+5V) are typically provided to the following parallel port signals:

STROBE-

SLIN-

INIT-

AUTOFD-

Generally, if the parallel port will be connected to a cable for high speed data communication (as opposed to static digital output levels or static TTL level sensing), certain signals require a 2.2 nF capacitor connected to ground. These include:

PD0-PD7

STRB-

Parallel port register are provided for the parallel port as appears from the table set out below:

Parallel Port Registers Signal Active DB25F Register Bit Name In/Out High/Low Pin DATA 0 PD0 I/O HIGH 2 (A + 0) 1 PD1 I/O HIGH 3 2 PD2 I/O HIGH 4 3 PD3 I/O HIGH 5 4 PD4 I/O HIGH 6 5 PD5 I/O HIGH 7 6 PD6 I/O HIGH 8 7 PD7 I/O HIGH 9 STATUS 0 1 — — — (A + 1)) 1 1 — — — 2 1 — — — 3 ERROR- IN LOW 15 4 SLCT- IN HIGH 13 5 PE IN HIGH 12 6 ACK- IN HIGH 10 7 BUSY IN LOW 11 CONTROL 0 STRB- OUT LOW 1 (A + 2) 1 AUTOFD- OUT LOW 14 2 INIT- OUT HIGH 16 3 SLCTIN- OUT LOW 17 4 IRQ ENABLE — HIGH — 5 1 — — — 6 1 — — — 7 1 — — —

The DOS-compatible floppy drive interface 40 allows cable connections for up to four floppy drives. In pC-compatible systems, the BIOS and DOS support two drives. These are configure using the BIOS SETUP function. Hardware controls for two additional drives are provided.

The floppy drive interface supports the following standard floppy formats:

Capacity Drive Size Tracks Data Rate 360K 5-1/4 inch 40 250 KHz 1.2M 5-1/4 inch 80 500 KHz 720K 3-1/2 inch 80 250 KHz 1.44M 3-1/2 inch 80 500 KHz

The various floppy interface resources are given in the table below

Floppy Interface Resources Resource Function I/O Address 3F2 FDC Digital Output Register (LDOR) 3F0h-3F7h 3F4 FDC Main Status Register 3F5 FDC Data Register 3F7 FDC Control Register (LDCR) IRQ6 Interrupt DRQ2BDACK2 DMA Controller Channel

Outputs to the floppy drive and from the floppy drive are Aopen collector≅. Pull-up resistors are therefore required for proper termination, both on the SMX/386 board and on one of the attached floppy drives (not both).

330-Ohm pull-ups are required for the following floppy interface signals:

DSKCHG-

RDATA-

WRPRT-

TRK0-

INDEX-

The pin numbers and functions associated with the floppy drive are given in the table below:

Floppy Drive Interface Floppy Pin Pin Signal Name Function In/Out 11 2 DENSEL Speed/Precomp 4 N/A N/A 6 N/S Key pin N/A 12 8 INDEX- Index Pulse IN 13 10 MTR0- Motor On 0 OUT 15 12 DRV1- Drive Select 2 OUT 18 14 DRV0- Drive Select 1 OUT 20 16 MTR1- Motor On 1 OUT 22 18 DIR- Direction Select OUT 23 20 STEP- Step Pulse OUT 24 22 WDATA- Write Data OUT 25 24 WGATE- Write Gate OUT 26 26 TRK0- Track 0 INPUT 27 28 WRPRT- Write Protect INPUT 28 30 RDATA- Read Data INPUT 29 32 HDSEL- Head Select OUT 30 34 DSKCHG- Disk Change INPUT 1B33 Ground Ground

The IDE hard drive interface 42 is a standard interface used in PC-compatible systems for haed disk drives. Up to two drives can be connected in a master-slave arrangement. The resources are depicted in the table below:

IDE Hard Disk Resources Resource Function I/O Address Hard Disk Interface 1F0h-1F7h IRQ14 Interrupt

The IDE interface pins are arranged to easily attach to a male PC-mounted ribbon-cable connector, the IDE drives typically being attached to the drive interface using a 40-pin ribbon cable.

The pin configuration for the IDE interface is given in the table below:

IDE Drive Interface IDE Pin Pin Signal Name Function In/Out 223 1 HDRESET- Reset signal from host OUT 2 GND Ground OUT 224 3 IDED7 Data bit 7 I/O 225 4 HDD08 Data bit 8 I/O 226 5 HDD06 Data bit 6 I/O 227 6 HDD09 Data bit 9 I/O 228 7 HDD05 Data bit 5 I/O 229 8 HDD10 Data bit 10 I/O 230 9 HDD04 Data bit 4 I/O 231 10 HDD11 Data bit 11 I/O 232 11 HDD03 Data bit 3 I/O 233 12 HDD12 Data bit 12 I/O 234 13 HDD02 Data bit 2 I/O 235 14 HDD13 Data bit 13 I/O 236 15 HDD01 Data bit 1 I/O 237 16 HDD14 Data bit 14 I/O 238 17 HDD00 Data bit 0 I/O 239 18 HDD15 Data bit 15 I/O 19 GND Ground OUT 20 KEY Keyed pin N/C 21 N/A Reserved N/C 22 GND Ground OUT 240 23 HDIOW- Write strobe OUT 24 GND Ground OUT 1 25 HDIOR- Read strobe OUT 26 GND Ground OUT 27 RSVD Reserved N/C 2 28 HDALE Address latch enable OUT 29 RSVD Reserved N/C 30 GND Ground OUT 237 31 HED 14 Drive interrupt request IN

One embodiment of the pin configuration for the module 10 as a whole is illustrated in FIG. 4 and is given in the pin description table below:

Pin Pin Name Description Type 1 HDIOR- IDE I/O Read, active low. Buffered version of O24 IOR 2 HDALE IDE Address Latch Enable, active high. O24 Buffered version of BALE 3 IRQ14 IDE Interrupt Request 14. For use with IDE I interface. Same signal appears on pin 90. 4 IOCS16 IDE I/O Chip Select 16. A low requests a I 16-bit transfer on the SA bus. Same signal appears on pin 238. This one is used for the IDE interface. 5 HDA1 IDE Address 1. Buffered version of SA1. O24 6 HDAO IDE Address 0. Buffered version of SA0 O24 7 HDA2 IDE Address 2. Buffered version of SA2 O24 8 HDCS- IDE Chip Select. A low indicates that data is O24 being transferred to or from the IDE drive. 9 FDCS- Floppy disk chip Select. A low indicates that O24 data is being transferred to or from the floppy disk. 10 LEDIN LED signal form IDE drive I 11 DENSEL 12 INDEX- Floppy disk index pulse, input from drive I 13 MTRO- Floppy disk active lower open drain output selects motor driver 0. The motor enable bits are software controlled via the floppy's Digital Output Register (DOR). 14 MTR2- Floppy disk active low open drain output selects motor driver 2. The motor enable bits are software controlled via the floppy's Digital Output Register (DOR). 15 DRV1- Floppy disk active lower open drain output that selects floppy drive 1 16 DRV3- Floppy disk active low open drain output that selects floppy drive 3 17 GND 18 DRV0- Floppy disk active low open drain output that selects floppy drive 0 19 DRV2- Floppy disk active low open drain output that selects floppy drive 2 20 MTR1- Floppy disk active low open drain output selects motor driver 1. The motor enable bits are software controlled via the floppy's Digital Output Register (DOR). 21 MTR3- Floppy disk active low open drain output selects motor driver 3. The motor enable bits are software controlled via the floppy's Digital Output Register (DOR). 22 DIR Floppy disk open drain output that controls floppy read/write head movement direction. Low = set pin. 23 STEP- Floppy disk active low output provides the step pulse to move the floppy read/write head 24 WDATA- Floppy disk active lower signal writes precompensated serial data to the selected floppy drive. This is a high open current drain output and is gated internally with WGATE-. 25 WGATE- Floppy disk active low open drain signal that enables the head to write onto the floppy disk. 26 TRK0- Floppy disk active lower Schmitt input IS indicates that the head is on track 0 of the selected drive 27 WRPRT- Floppy disk active low Schmitt input indicating IS that the disk is write protected. Any WDATA- command is ignored. 28 RDATA- Floppy disk active lower Schmitt input that IS reads raw data from the floppy disk. 29 HDSEL Floppy disk open drain output that selects the head on the selected drive. Low = side 0. 30 DSKCHG Floppy disk input signal indicating that the I floppy door has been opened. 31 5VBB 32 GND 33 PFI Powerfail 34 PFO Powerfail 35 MR- Powerfail 36 RTCIRQ Alarm output from the onboard real time clock 37 WDO Watchdog timer 38 SA00 ISA System Address 00 O24 39 OSC ISA 14.318 MHz clock. This clock is asynchronous to all other system clocks 40 SA01 ISA System Address 01 O24 41 SA02 ISA System Address 02 O24 42 BALE ISA Buffered Address Latch Enable 43 SA03 ISA System Address 03 O24 44 SD15 ISA System Data 15 45 TC ISA DMA Terminal Court 46 SA04 ISA System Address 04 O24 47 MASTER- ISA 48 SD14 ISA System Data 14 49 DACK2- ISA DMA 2 Acknowledge strobe 50 SA05 ISA System Address 05 O24 51 SD13 ISA System Data 13 52 IRQ3 ISA Interrupt Request 3 I 53 SA06 ISA System Address 06 O24 54 DRQ7 ISA DMA 7 Request I 55 SD12 ISA System Data 12 56 IRQ4 ISA Interrupt Request 4 I 57 SA07 ISA System Address 07 O24 58 DACK7- ISA DMA 7 Acknowledge strobe 59 SD11 ISA System Data 11 60 IRQ5 ISA Interrupt Request 5 I 61 SA08 ISA System Address 08 O24 62 DRQ6 ISA DMA 6 Request I 63 SD10 ISA System Data 10 64 IRQ6OUT Floppy disk interrupt request. Normally connects to IRQ6 (pin 65) 65 IRQ6 ISA Interrupt Request 6 I 66 SA09 ISA System Address 09 O24 67 GND 68 DACK6- ISA DMA 6 Acknowledge strobe 69 SD09 ISA System Data 09 70 IRQ7OUT Parallel port interrupt request. Normally connects to IRQ7 (pin 71). 71 IRQ7 ISA Interrupt Request 7 I 72 SA10 ISA System Address 10 O24 73 DRQ5 ISA DMA 5 Request I 74 SD08 ISA System Data 08 75 SYSCLK ISA System clock 76 SA11 ISA System Address 11 O24 77 DACK5- ISA DMA 5 Acknowledge strobe 78 MEMW- ISA active low memory write strobe 79 RE- ISA active low signal indicating current bus FRESH- cycle is a memory refresh 80 SA12 ISA System Address 12 O24 81 DRQO ISA DMA 0 Request I 82 MEMR- ISA active low memory read strobe 83 DRQ1 ISA DMA 1 Request I 84 SA13 ISA System Address 13 O24 85 VCC 86 DACKO- ISA DSMA 0 Acknowledge strobe 87 LA17 ISA Latched Address 17 O24 88 DACK1- ISA DMA 1 Acknowledge strobe 89 SA14 ISA System Address 14 O24 90 IRQ14 ISA Interrupt Request 14, normally used for I IDE interface 91 LA18 ISA Latched address 18 O24 92 DRQ3 ISA DMA 3 Request strobe 93 SA15 ISA System Address 15 O24 94 IRQ15 ISA Interrupt Request 15 I 95 LA19 ISA Latched Address 19 O24 96 DACK3- ISA DMA 3 Acknowledge strobe 97 SA16 ISA System Address 16 O24 98 IRQ12 ISA Interrupt Request 12 I 99 LA20 ISA Latched Address 20 O24 100 IOR- ISA I/O Read strobe 101 SA17 ISA System Address 17 O24 102 GND 103 IRQ11 ISA Interrupt Request 11 I 104 LA21 ISA Latched Address 21 O24 105 IOW- ISA I/O Write strobe 106 SA18 ISA System Address 18 O24 107 IRQ10 ISA Interrupt Request 10 I 108 LA22 ISA Latched Address 22 O24 109 SMEMR- ISA System Memory Read strobe 110 SA19 ISA System Address 19 O24 111 IOCS16- ISA 16-bit I/O Chip Select request Indicates I that the current I/O transaction is 16-bits. 112 LA23 ISA Latched Address 23 O24 113 SMEMW- ISA System Memory Write strobe 114 AEN ISA Address Enable 115 MEMCS- ISA 16-bit Memory Chip Select request. I 16 Indicates that the current memory transaction is 16-bits. 116 SBHE- ISA System Byte High Enable 117 IOCH- ISA I/O Channel Ready. A low adds wait states I RDY to the current ISA bus cycle 118 SD00 ISA System Data 00 119 0WS ISA active low causing current memory cycle I to be completed without additional wait states. 120 SD01 ISA System Data 01 121 SD02 ISA System Data 02 122 DRQ2 Floppy DMA 2 Request Normally connected to OUT DRQ2 (pin 123) 123 DRQ2 ISA DMA 2 Request strobe I 124 SD03 ISA System Data 03 125 SD04 ISA System Data 04 126 IRQ9 ISA Interrupt Request 09 I 127 SD05 ISA System Data 05 128 SD06 ISA System Data 06 129 RESET ISA active high system reset signal DRV 130 SD07 ISA System Data 07 131 IOCH- ISA gated non-maskable interrupt input I CHK- 132 HISPEED Input to select CPU speed. High = high speed. I 133 SPKR Speaker output 134 KDATA Keyboard data 135 KCLOCK Keyboard clock 136 PWRDN- 137 GND 138 COLOR Video Color/Mono jumper I 139 KBLOCK Keyboard lock. Low blocks keyboard input I 140 SLCT Parallel Port 141 PE Parallel Port 142 BUSY Parallel Port 143 ACK- Parallel Port 144 PD7 Parallel Port Data 7 145 PD6 Parallel Port Data 6 146 PD5 Parallel Port Data 5 147 PD4 Parallel Port Data 4 148 PD3 Parallel Port Data 3 149 SLCTIN- Parallel Port 150 PD2 Parallel Port Data 2 151 INIT- Parallel Port 152 PD1 Parallel Port Data 1 153 ERR- Parallel Port 154 GND 155 PD0 Parallel Port Data 0 156 AUTOFD Parallel Port 157 STRB- Parallel Port 158 DCD2 Serial Port 2 Data Carrier Detect 159 DSR2 Serial Port 2 Data Set Ready 160 RXD2 Serial Port 2 Receive Data 161 RTS2 Serial Port 2 Request To Send 162 TXD2 Serial Port 2 Transmit Data 163 CTS2 Serial Port 2 Clear To Send 164 DTR2 Serial Port 2 Data Terminal Ready 165 R12 Serial Port 2 Ring Indicator 166 DCD1 Serial Port 1 Data Carrier Detect 167 DSR1 Serial Port 1 Data Set Ready 168 RXD1 Serial Port 1 Receive Data 169 RTS1 Serial Port 1 Request to Send 170 TXD1 Serial Port 1 Transmit Data 171 CTS1 Serial Port 1 Clear to Send 172 DTR1 Serial Port 1 Data Terminal Ready 173 RI1 Serial Port 1 Ring Indicator 174 GAME- CS- 175 RAS3- DRAM Row Address Strobe 3 176 RAS2- DRAM Row Address Strobe 2 177 RAS1- DRAM Row Address Strobe 1 178 RAS0- DRAM Row Address Strobe 0 179 DP1 DRAM parity bit for high byte memory 180 DP0 DRAM parity bit for low byte memory 181 D15 DRAM Data Bit 15 182 D07 DRAM Data Bit 7 183 D14 DRAM Data Bit 14 184 D06 DRAM Data Bit 6 185 DRWE- DRAM memory write strobe 186 D13 DRAM Data Bit 13 187 GND 188 D05 DRAM Data Bit 5 189 MA10 DRAM multiplexed memory address 10 190 MA09 DRAM multiplexed memory address 9 191 MA08 DRAM multiplexed memory address 8 192 D12 DRAM Data Bit 12 193 D04 DRAM Data Bit 4 194 MA07 DRAM multiplexed memory address 7 195 MA06 DRAM multiplexed memory address 6 196 D11 DRAM Data Bit 11 197 D03 DRAM Data Bit 3 198 MA05 DRAM multiplexed memory address 5 199 MA04 DRAM multiplexed memory address 4 200 D10 DRAM Data Bit 10 201 D01 DRAM Data Bit 2 202 MA03 DRAM multiplexed memory address 3 203 MA02 DRAM multiplexed memory address 2 204 D09 DRAM Data Bit 9 205 VCC 206 D01 DRAM Data Bit 1 207 MA01 DRAM multiplexed memory address 1 208 MA00 DRAM multiplexed memory address 0 209 D08 DRAM Data Bit 8 210 D00 DRAM Data Bit 0 211 CASH3- DRAM Column Address Strobe, High byte 3 212 CASL3- DRAM Column Address Strobe, Low byte 3 213 CASH2- DRAM Column Address Strobe, High byte 2 214 CASL2- DRAM Column Address Strobe, Low byte 2 215 CASH1- DRAM Column Address Strobe, High byte 1 216 CASL1- DRAM Column Address Strobe, Low byte 1 217 CASH0- DRAM Column Address Strobe, High byte 0 218 CASL0- DRAM Column Address Strobe, Low byte 0 219 BDIS 220 XROM- CS- 221 LEDOUT- 222 GND 223 HDRE- IDE SET- 224 IDED07 IDE Data Bit 7 225 HDD08 IDE Data Bit 8 226 HDD06 IDE Data Bit 6 227 HDD09 IDE Data Bit 9 228 HDD05 IDE Data Bit 5 229 HDD10 IDE Data Bit 10 230 HDD04 IDE Data Bit 4 231 HDD11 IDE Data Bit 11 232 HDD03 IDE Data Bit 3 233 HDD12 IDE Data Bit 12 234 HDD02 IDE Data Bit 2 235 HDD13 IDE Data Bit 13 236 HDD01 IDE Data Bit 1 237 HED14 IDE Data Bit 14 238 HDD00 IDE Data Bit 0 239 HDD15 IDE Data Bit 15 240 HDIOW- IDE buffered I/O Write strobe

As mentioned above, the core logic 26 supports a DRAM bus 22 and an ISA compatible expansion bus 24 complying in number and signal type with the IEEE-P996 requirements (and corresponding to the ISA (Industry Standard Architecture) requirements). The pin configuration for the expansion bus 24 is given in the table below with corresponding pin numbers for expansion bus connectors A, B, C, D. The bus 24 comprises 94 pins that includes VCC and two GND pins.

Signal In/ Pin Name Function Out Current Load* 38 A31 SA00 Address bit 0 I/O 12 mA PU 39 B30 OSC 14.318 MHz clock Out  6 mA 33 SER 40 A30 SA01 Address bit 1 I/O 12 mA PU 41 A29 SA02 Address bit 2 I/O 12 mA PU 42 B28 BALE Address latch enable Out 12 mA 43 A28 SA03 Address bit 3 I/O 12 mA PU 44 C18 SD15 System Data bit 15 I/O 12 mA PU 45 B27 TC DMA Terminal Out  4 mA Count 46 A27 SA04 Address bit 4 I/O 12 mA PU 47 D17 MAS- Bus master assert In N/A 330 PU TER- 48 C17 SD14 System Data bit 14 I/O 24 mA PU 49 B26 DACK- DMA Acknowledge 2 Out  4 mA 2- 50 A26 SA05 Address bit 5 I/O 12 mA PU 51 C16 SD13 System Data bit 13 I/O 24 mA PU 52 B25 IRQ3 Interrupt Request 3 In N/A PU 53 A25 SA06 Address bit 6 I/O 12 mA PU 54 D15 DRQ7 DMA Request 7 In N/A PD 55 C15 SD12 System Data bit 12 I/O 24 mA PU 56 B24 IRQ4 Interrupt Request 4 In N/A PU 57 A24 SA07 Address bit 7 I/O 12 mA PU 58 D14 DACK- DMA Acknowledge 7 Out  4 mA 7- 59 C14 SD11 System Data bit 11 I/O 24 mA PU 60 B23 IRQ5 Interrupt Request 5 In N/A PU 61 A23 SA08 Address bit 8 I/O 12 mA PU 62 D13 DRQ6 DMA Request 6 In N/A PD 63 C13 SD10 System Data bit 10 I/O 24 mA PU 64 IRQ6- Floppy Disk Interrupt OUT Request 65 B22 IRQ6 Interrupt Request 6 In N/A PU 66 A22 SA09 Address bit 9 I/O 12 mA PU 67 GND 68 D12 DACK- DMA Acknowledge 6 Out  4 mA 6- 69 C12 SD9 System Data bit 9 I/O 24 mA PU 70 IRQ7- Parallel Port Interrupt OUT Request 71 B21 IRQ7 Interrupt Request 7 In N/A PU 72 A21 SA10 Address bit 10 I/O 12 mA PU 73 D11 DRQ5 DMA Request 5 In N/A PD 74 C11 SD08 System Data bit 8 I/O 24 mA PU 75 B20 SYS- System clock (8 Out 12 mA CLK MHz) 76 A20 SA11 Address bit 11 I/O 12 mA PU 77 D10 DACK- DMA Acknowledge 5 Out  4 mA 5- 78 C10 MEM- Memory Write I/O  6 mA PU, 33 W SER 79 B19 REFR- Memory Refresh I/O  6 mA 470 PU, ESH- 33 SER 80 A19 SA12 Address bit 12 I/O 12 mA PU 81 D9 DRQ0 DMA Request 0 In N/A PD 82 C9 MEMR- Memory Read I/O  6 mA PU, 33 SER 83 B18 DRQ1 DMA Request 1 In N/A PD 84 A18 SA13 Address bit 13 I/O 12 mA PU 85 VCC 86 D8 DACK- DMA Acknowledge 0 Out  4 mA 0- 87 C8 LA17 Address bit 17 I/O 24 mA 88 B17 DACK- DMA Acknowledge 1 Out  4 mA 1- 89 A17 SA14 Address bit 14 I/O 12 mA PU 90 D7 IRQ14 Interrupt Request 14 In N/A PU 91 C7 LA18 Address bit 18 I/O 24 mA 92 B16 DRQ3 DMA Request 3 In N/A PD 93 A16 SA15 Address bit 15 I/O 12 mA PU 94 D6 IRQ15 Interrupt Request 15 In N/A PU 95 C6 LA19 Address bit 19 I/O 24 mA 96 B15 DACK- DMA Acknowledge 3 Out  4 mA 3- 97 A15 SA16 Address bit 16 I/O 12 mA PU 98 D5 IRQ12 Interrupt Request 12 In N/A PU 99 C5 LA20 Address bit 20 I/O 24 mA 100 B14 IOR- I/O Read I/O  6 mA PU 101 A14 SA17 Address bit 17 I/O 12 mA PU 102 GND 103 D4 IRQ11 Interrupt Request 11 In N/A PU 104 C4 LA21 Address bit 21 I/O 24 mA 105 B13 IOW- I/O Write I/O  6 mA PU 106 A13 SA18 Address bit 18 I/O 12 mA PU 107 D3 IRQ10 Interrupt Request 10 In N/A PU 108 C3 LA22 Address bit 22 I/O 24 mA 109 B12 SME- Mem Read (lower I/O  6 mA 33 SER MR- 1MB) 110 A12 SA19 Address bit 19 I/O 12 mA PU 111 D2 IOCS- 16-bit I/O access In N/A 330 PU 16- 112 C2 LA23 Address bit 23 I/O 24 mA 113 B11 SMEM- Mem Write (lower 1 I/O  6 mA 33 SER W MB) 114 A11 AEN Address Enable I/O 12 mA PU 115 D1 MEMC- 16-bit mem access In N/A 330 PU S16- 116 C1 SBHE- Bus High Enable I/O 12 mA PU 117 A10 IOCH Processor Ready Ctrl In N/A 1K PU RDY 118 A9 SD00 System Data bit 0 I/O 24 mA PU 119 B8 END- Zero wait state I/O N/A 330 PU XFR (OWS-) 120 A8 SD01 System Data bit 1 I/O 24 mA PU 121 A7 SD02 System Data bit 2 I/O 24 mA PU 122 DRQ2 Floppy DMA 2 OUT Request 123 B6 DRQ2 DMA request 2 In N/A PD 124 A6 SD03 System Data bit 3 I/O 24 mA PU 125 A5 SD04 System Data bit 4 I/O 24 mA PU 126 B4 IRQ9 Interrupt request 9 In N/A PU 127 A4 SD05 System Data bit 5 I/O 24 mA PU 128 A4 SD06 System Data bit 6 I/O 24 mA PU 129 B2 RESET System reset signal Out 24 mA DRY 130 A2 SD07 System Data bit 7 I/O 24 mA PU 131 A1 IOCH- Sub NMI input In N/A 4.7K CK- PU

An alternative embodiment of the pin configuration for the module 10 as a whole is illustrated in FIG. 5 and is given in the pin description table below:

Pin Pin Name Description Type 1 HDIOR- IDE I/O Read, active low. Buffered version of O24 IOR 2 HDALE IDE Address Latch Enable, active high. O24 Buffered version of BALE 3 IRQ14 IDE Interrupt Request 14. For use with IDE I interface. Same signal appears on pin 90. 4 IOCS16- IDE I/O Chip Select 16. A low requests a 16- I bit transfer on the SA bus. Same signal appears on pin 238. This one is used for the IDE interface. 5 HDA1 IDE Address 1. Buffered version of SA1. O24 6 HDA0 IDE Address 0. Buffered version of SA0 O24 7 HDA2 IDE Address 2. Buffered version of SA2 O24 8 HDCS- IDE Chip Select. A low indicates that data is O24 being transferred to or from the IDE drive. 9 FDCS- Floppy disk Chip Select. A low indicates that O24 data is being transferred to or from the floppy disk. 10 LEDIN LED signal from IDE drive I 11 DENSEL 12 INDEX- Floppy disk index pulse, input from drive I 13 MTR0- Floppy disk active lower open drain output selects motor driver 0. The motor enable bits are software controlled via the floppy's Digital Output Register (DOR). 14 MTR2- Floppy disk active low open drain output selects motor driver 2. The motor enable bits are software controlled via the floppy's Digital Output Register (DOR). 15 DRV1 - Floppy disk active lower open drain output that selects floppy drive 1 16 DRV3- Floppy disk active low open drain output that selects floppy drive 3 17 GND 18 DRV0- Floppy disk active low open drain output that selects floppy drive 0 19 DRV2- Floppy disk active low open drain output that selects floppy drive 2 20 MTR1- Floppy disk active low open drain output selects motor driver 1. The motor enable bits are software controlled via the floppy's Digital Output Register (DOR). 21 MTR3- Floppy disk active low open drain output selects motor driver 3. The motor enable bits are software controlled via the floppy's Digital Output Register (DOR). 22 DIR Floppy disk open drain output that controls floppy read/write head movement direction. Low = set pin. 23 STEP- Floppy disk active low output provides the step pulse to move the floppy read/write head 24 WDATA- Floppy disk active lower signal writes precompensated serial data to the selected floppy drive. This is a high open current drain output and is gated internally with WGATE-. 25 WGATE- Floppy disk active low open drain signal that enables the head to write onto the floppy disk. 26 TRK0- Floppy disk active lower Schmitt input IS indicates that the head is on track 0 of the selected drive 27 WRPRT- Floppy disk active low Schmitt input indicating IS that the disk is write protected. Any WDATA- command is ignored. 28 RDATA- Floppy disk active lower Schmitt input that IS reads raw data from the floppy disk. 29 HDSEL Floppy disk open drain output that selects the head on the selected drive. Low = side 0. 30 DSKCHG Floppy disk input signal indicating that the I floppy door has been opened. 31 5VBB 32 GND 33 PFI Powerfail 34 PFO Powerfail 35 MR- Powerfail 36 RTCIRQ- Alarm output from the onboard real time clock 37 WDO Watchdog timer 38 IOCHCK ISA System Address 00 O24 39 SD07 ISA 14.318 MHz clock. This clock is asynchronous to all other system clocks 40 RESET- ISA System Address 01 O24 DRV 41 SD06 ISA System Address 02 O24 42 SD05 ISA Buffered Address Latch Enable 43 IRQ9 ISA System Address 03 O24 44 SD04 ISA System Data 15 45 SD03 ISA DMA Terminal Court 46 DRQ2 ISA System Address 04 O24 47 DRQ2- ISA OUT- 48 SD02 ISA System Data 14 49 SD01- ISA DMA 2 Acknowledge strobe 50 0WS ISA System Address 05 O24 51 SD00 ISA System Data 13 52 IOCH- ISA Interrupt Request 3 I RDY 53 SBHE- ISA System Address 06 O24 54 MEMC- ISA DMA 7 Request I S16 55 AEN ISA System Data 12 56 SMEMW- ISA Interrupt Request 4 I 57 LA23 ISA System Address 07 O24 58 IOCS16- ISA DMA 7 Acknowledge strobe 59 SA19 ISA System Data 11 60 SMEMR- ISA Interrupt Request 5 I 61 LA22 ISA System Address 08 O24 62 IRQ10 ISA DMA 6 Request I 63 SA18 ISA System Data 10 64 IOW- Floppy disk interrupt request. Normally connects to IRQ6 (pin 65) 65 LA21 ISA Interrupt Request 6 I 66 IRQ11 ISA System Address 09 O24 67 GND 68 SA17 ISA DMA 6 Acknowledge strobe 69 IOR- ISA System Data 09 70 LA20 Parallel port interrupt request. Normally connects to IRQ7 (pin 71). 71 IRQ12 ISA Interrupt Request 7 I 72 SA16 ISA System Address 10 O24 73 DACK3- ISA DMA 5 Request I 74 LA19 ISA System Data 08 75 IRQ15 ISA System Clock 76 SA15 ISA System Address 11 O24 77 DRQ3 ISA DMA 5 Acknowledge strobe 78 LA18 ISA active low memory write strobe 79 IRQ14 ISA active low signal indicating current bus cycle is a memory refresh 80 SA14 ISA System Address 12 O24 81 DACK1- ISA DMA 0 Request I 82 LA17 ISA active low memory read strobe 83 DACK0- ISA DMA 1 Request I 84 SA13 ISA System Address 13 O24 85 VCC 86 DRQ1 ISA DSMA 0 Acknowledge strobe 87 MEMR- ISA Latched Address 17 O24 88 DRQ0 ISA DMA 1 Acknowledge strobe 89 SA12 ISA System Address 14 O24 90 RE- ISA Interrupt Request 14, normally used for I FRESH- IDE interface 91 MEMW- ISA Latched address 18 O24 92 DACK5- ISA DMA 3 Request strobe 93 SA11 ISA System Address 15 O24 94 SYSCLK ISA Interrupt Request 15 I 95 SD08 ISA Latched Address 19 O24 96 DRQ5 ISA DMA 3 Acknowledge strobe 97 SA10 ISA System Address 16 O24 98 IRQ7 ISA Interrupt Request 12 I 99 IRQ7OUT ISA Latched Address 20 O24 100 SD09 ISA I/O Read strobe 101 DACK6- ISA System Address 17 O24 102 GND 103 SA09 ISA Interrupt Request 11 I 104 IRQ6 ISA Latched Address 21 O24 105 IRQ6OUT ISA I/O Write strobe 106 SD10 ISA System Address 18 O24 107 DRQ6 ISA Interrupt Request 10 I 108 SA08 ISA Latched Address 22 O24 109 IRQ5 ISA System Memory Read strobe 110 SD11 ISA System Address 19 O24 111 DACK7- ISA 16-bit I/O Chip Select request. Indicates I that the current I/O transaction is 16-bits. 112 SA07 ISA Latched Address 23 O24 113 IRQ4 ISA System Memory Write strobe 114 SD12 ISA Address Enable 115 DRQ7 ISA 16-bit Memory Chip Select request. I Indicates that the current memory transaction is 16-bits. 116 SA06 ISA System Byte High Enable 117 IRQ3 ISA I/O Channel Ready. A low adds wait states I to the current ISA bus cycle 118 SD13 ISA System Data 00 119 SA05 ISA active low causing current memory cycle I to be completed without additional wait states. 120 DACK2- ISA System Data 01 121 SD14 ISA System Data 02 122 MASTER- Floppy DMA 2 Request. Normally connected to DRQ2 (pin 123) 123 SA04 ISA DMA 2 Request strobe I 124 TC ISA System Data 03 125 SD15 ISA System Data 04 126 SA03 ISA Interrupt Request 09 I 127 BALE ISA System Data 05 128 SA02 ISA System Data 06 129 SA01 ISA active high system reset signal 130 OSC ISA System Data 07 131 SA00 ISA gated non-maskable interrupt input I 132 HISPEED Input to select CPU speed. High-high speed. I 133 SPKR Speaker output 134 KDATA Keyboard data 135 KCLOCK Keyboard clock 136 PWRDN- 137 GND 138 COLOR Video Color/Mono jumper 139 KBLOCK Keyboard lock. Low blocks keyboard input 140 SLCT Parallel Port 141 PE Parallel Port 142 BUSY Parallel Port 143 ACK- Parallel Port 144 PD7 Parallel Port Data 7 145 PD6 Parallel Port Data 6 146 PD5 Parallel Port Data 5 147 PD4 Parallel Port Data 4 148 PD3 Parallel Port Data 3 149 SLCTIN- Parallel Port 150 PD2 Parallel Port Data 2 151 INIT- Parallel Port 152 PD1 Parallel Port Data 1 153 ERR- Parallel Port 154 GND 155 PD0 Parallel Port Data 0 156 AUTOFD Parallel Port 157 STRB- Parallel Port 158 DCD2 Serial Port 2 Data Carrier Detect 159 DSR2 Serial Port 2 Data Set Ready 160 RXD2 Serial Port 2 Receive Data 161 RTS2 Serial Port 2 Request To Send 162 TXD2 Serial Port 2 Transmit Data 163 CTS2 Serial Port 2 Clear To Send 164 DTR2 Serial Port 2 Data Terminal Ready 165 R12 Serial Port 2 Ring Indicator 166 DCD1 Serial Port 1 Data Carrier Detect 167 DSR1 Serial Port 1 Data Set Ready 168 RXD1 Serial Port 1 Receive Data 169 RTS1 Serial Port 1 Request to Send 170 TXD1 Serial Port 1 Transmit Data 171 CTS1 Serial Port 1 Clear to Send 172 DTR1 Serial Port 1 Data Terminal Ready 173 RI1 Serial Port 1 Ring Indicator 174 GAMECS 175 RAS3- DRAM Row Address Strobe 3 176 RAS2- DRAM Row Address Strobe 2 177 RAS1- DRAM Row Address Strobe 1 178 RAS0- DRAM Row Address Strobe 0 179 DP1 DRAM parity bit for high byte memory 180 DP0 DRAM parity bit for low byte memory 181 D15 DRAM Data Bit 15 182 D07 DRAM Data Bit 7 183 D14 DRAM Data Bit 14 184 D06 DRAM Data Bit 6 185 DRWE- DRAM memory write strobe 186 D13 DRAM Data Bit 13 187 GND 188 D05 DRAM Data Bit 5 189 MA10 DRAM multiplexed memory address 10 190 MA09 DRAM multiplexed memory address 9 191 MA08 DRAM multiplexed memory address 8 192 D12 DRAM Data Bit 12 193 D04 DRAM Data Bit 4 194 MA07 DRAM multiplexed memory address 7 195 MA06 DRAM multiplexed memory address 6 196 D11 DRAM Data Bit 11 197 D03 DRAM Data Bit 3 198 MA05 DRAM multiplexed memory address 5 199 MA04 DRAM multiplexed memory address 4 200 D10 DRAM Data Bit 10 201 D01 DRAM Data Bit 2 202 MA03 DRAM multiplexed memory address 3 203 MA02 DRAM multiplexed memory address 2 204 D09 DRAM Data Bit 9 205 VCC 206 D01 DRAM Data Bit 1 207 MA01 DRAM multiplexed memory address 1 208 MA00 DRAM multiplexed memory address 0 209 D08 DRAM Data Bit 8 210 D00 DRAM Data Bit 0 211 CASH3- DRAM Column Address Strobe, High byte 3 212 CASL3- DRAM Column Address Strobe, Low byte 3 213 CASH2- DRAM Column Address Strobe, High byte 2 214 CASL2- DRAM Column Address Strobe, Low byte 2 215 CASH1- DRAM Column Address Strobe, High byte 1 216 CASL1- DRAM Column Address Strobe, Low byte 1 217 CASH0- DRAM Column Address Strobe, High byte 0 218 CASL0- DRAM Column Address Strobe, Low byte 0 219 BDIS 220 XRO- MCS- 221 LEDOUT- 222 GND 223 HDRE- IDE SET- 224 IDED07 IDE Data Bit 7 225 HDD08 IDE Data Bit 8 226 HDD06 IDE Data Bit 6 227 HDD09 IDE Data Bit 9 228 HDD05 IDE Data Bit 5 229 HDD10 IDE Data Bit 10 230 HDD04 IDE Data Bit 4 231 HDD11 IDE Data Bit 11 232 HDD03 IDE Data Bit 3 233 HDD12 IDE Data Bit 12 234 HDD02 IDE Data Bit 2 235 HDD13 IDE Data Bit 13 236 HDD01 IDE Data Bit 1 237 HDD14 IDE Data Bit 14 238 HDD00 IDE Data Bit 0 239 HDD15 IDE Data Bit 15 240 HDIOW- IDE buffered I/O Write strobe

A second embodiment of the pin configuration for the expansion bus 24 is given in the table below with corresponding pin numbers for expansion bus connectors A, B, C, D. As mentioned before, bus 24 comprises 94 pins that includes VCC and two GND pins.

Signal Pin Name Function In/Out Current Load* 38 A31 IOCHCK Address bit 0 I/O 12 mA PU 39 B30 SD07 14.318 MHz Out  6 mA 33 SER clock 40 A30 RESET- Address bit 1 I/O 12 mA PU DRV 41 A29 SD06 Address bit 2 I/O 12 mA PU 42 B28 SD05 Address latch Out 12 mA enable 43 A28 IRQ9 Address bit 3 I/O 12 mA PU 44 C18 SD04 System Data I/O 12 mA PU bit 15 45 B27 SD03 DMA Terminal Out  4 mA Count 46 A27 DRQ2 Address bit 4 I/O 12 mA PU 47 D17 DRQ2- Bus master In N/A 330 PU OUT- assert 48 C17 SD02 System Data I/O 24 mA PU bit 14 49 B26 SD01- DMA Out  4 mA Acknowledge 2 50 A26 0WS Address bit 5 I/O 12 mA PU 51 C16 SD00 System Data I/O 24 mA PU bit 13 52 B25 IOCH- Interrupt In N/A PU RDY Request 3 53 A25 SBHE- Address bit 6 I/O 12 mA PU 54 D15 MEMC- DMA Request 7 In N/A PD S16 55 C15 AEN System Data I/O 24 mA PU bit 12 56 B24 SMEMW- Interrupt In N/A PU Request 4 57 A24 LA23 Address bit 7 I/O 12 mA PU 58 D14 IOCS16 DMA Out  4 mA Acknowledge 7 59 C14 SA19 System Data I/O 24 mA PU bit 11 60 B23 SMEMR- Interrupt In N/A PU Request 5 61 A23 LA22 Address bit 8 I/O 12 mA PU 62 D13 IRQ10 DMA Request 6 In N/A PD 63 C13 SA18 System Data I/O 24 mA PU bit 10 64 IOW- Floppy Disk Interrupt Request 65 B22 LA21 Interrupt In N/A PU Request 6 66 A22 IRQ11 Address bit 9 I/O 12 mA PU 67 GND 68 D12 SA17 DMA Out  4 mA Acknowledge 6 69 C12 IOR- System Data bit 9 I/O 24 mA PU 70 LA20 Parallel Port Interrupt Request 71 B21 IRQ12 Interrupt In N/A PU Request 7 72 A21 SA16 Address bit 10 I/O 12 mA PU 73 D11 DACK3- DMA Requests 5 In N/A PD 74 C11 LA19 System Data bit 8 I/O 24 mA PU 75 B20 IRQ15 System clock (8 Out 12 mA MHz) 76 A20 SA15 Address bit 11 I/O 12 mA PU 77 D10 DRQ3 DMA Out  4 mA Acknowledge 5 78 C10 LA18 Memory Write I/O  6 mA PU. 33 SER 79 B19 IRQ14 Memory Refresh I/O  6 mA 470 PU. 33 SER 80 A19 SA14 Address bit 12 I/O 12 mA PU 81 D9 DACK1- DMA Request 0 In N/A PD 82 C9 LA17 Memory Read I/O  6 mA PU. 33 SER 83 B18 DACK0- DMA Request 1 In N/A PD 84 A18 SA13 Address bit 13 I/O 12 mA PU 85 VCC 86 D8 DRQ1- DMA Out  4 mA Acknowledge 0 87 C8 MEMR- Address bit 17 I/O 24 mA 88 B17 DRQ0 DMA Out  4 mA Acknowledge 1 89 A17 SA12 Address bit 14 I/O 12 mA PU 90 D7 RE- Interrupt In N/A PU FRESH- Request 14 91 C7 MEMW- Address bit 18 I/O 24 mA 92 B16 DACK5- DMA Request 3 In N/A PD 93 A16 SA11 Address bit 15 I/O 12 mA PU 94 D6 SYSCLK Interrupt In N/A PU Request 15 95 C6 SD08 Address bit 19 I/O 24 mA 96 B15 DRQ5 DMA Out  4 mA Acknowledge 3 97 A15 SA10 Address bit 16 I/O 12 mA PU 98 D5 IRQ7 Interrupt In N/A PU Request 12 99 C5 IRQ7OUT Address bit 20 I/O 24 mA 100 B14 SD09 I/O Read I/O  6 mA PU 101 A14 DACK6- Address bit 17 I/O 12 mA PU 102 GND 103 D4 SA09 Interrupt In N/A PU Request 11 104 C4 IRQ6 Address bit 21 I/O 24 mA 105 B13 IRQ6OUT I/O Write I/O  6 mA PU 106 A13 SD10 Address bit 18 I/O 12 mA PU 107 D3 DRQ6 Interrupt In N/A PU Request 10 108 C3 SA08 Address bit 22 I/O 24 mA 109 B12 IRQ5 Mem Read (lower I/O  6 mA 33 SER 1 MB) 110 A12 SD11 Address bit 19 I/O 12 mA PU 111 D2 DACK7- 16-bit I/O access In N/A 330 PU 112 C2 SA07 Address bit 23 I/O 24 mA 113 B11 IRQ4 Mem Write I/O  6 mA 33 SER (lower 1 MB) 114 A11 SD12 Address Enable I/O 12 mA PU 115 D1 DRQ7 16-bit mem In N/A 330 PU access 116 C1 SA06 Bus High Enable I/O 12 mA PU 117 A10 IRQ3 Processor In N/A 1K PU Ready Ctrl 118 A9 SD13 System Data bit 0 I/O 24 mA PU 119 B8 SA05 Zero wait state In N/A 330 PU 120 A8 DACK2- System Data bit 1 I/O 24 mA PU 121 A7 SD14 System Data bit 2 I/O 24 mA PU 122 MASTER- Floppy DMA 2 Request 123 B6 SA04 DMA request 2 In N/A PD 124 A6 TC System Data bit 3 I/O 24 mA PU 125 A5 SD15 System Data bit 4 I/O 24 mA PU 126 B4 SA03 Interrupt In N/A PU request 9 127 A4 BALE System Data I/O 24 mA PU bit 5 128 A4 SA02 System Data bit 6 I/O 24 mA PU 129 B2 SA01 System reset Out 24 mA signal 130 A2 OSC System Data bit I/O 24 mA PU 7- 131 A1 SA00 Sub NMI input In N/A 4.7K PU

The exact pin configuration as illustrated for the expansion bus on FIG. 5 is a critical feature of the invention. Since it forms a single row of pins on the module 10, the pins can be easily connected directly to the expansion bus connectors without having to resort to multiple layer boards to route the PC board tracks from the module 10 to the expansion bus connectors A, B, C, D. Furthermore, as mentioned above, the present invention includes both microprocessor modules as illustrated in FIG. 3, as well as peripheral controller modules such as display controller modules, Ethernet control modules, and PCMCIA compatible modules for extended memory (RAM, ROM, EEPROM, flash memory, etc.), as well as for modem, fax, and network interfaces, and also for wireless communication devices. By providing an identical pin configuration for the ISA buses, the various modules can easily be connected to one another.

A further feature of the invention is illustrated in FIG. 6. FIG. 6 illustrates a card 54 having a mounting site 56 for a module having a pin configuration as described above with reference to FIG. 4. The card 54 provides an integrated way for system development in standard ISA passive backplane systems. The card includes an AT-bus and a PC/104 bus, and occupies a single slot in an AT-class (16-bit) passive backplane. This allows development tQ be performed using a terminal on a serial port as a console. A standard VGA or SVGA display controller can be plugged into another slot on the backplane if desired. Instead, a PC/104 display controller can be installed directly on the PC/104 header 58 on the card 54. Since the module 10 is fully compatible with PC/AT ISA, a wide selection of hardware peripherals may be integrated. The ISA-compatible bus allows an OEM to easily interface his proprietary hardware design with the module 10. Futhermore, the standard BIOS and embedded DOS allows application software to be developed using standard desk top PCs and standard development tools for implementation on the system using one or more modules of the present invention. It will be appreciated that, depending on the nature of the module, the size of the module and the number of pins may vary, however it is an important feature of this invention that the pins for the ISA bus retain their configuration in each module to allow the modules to be readily connected to one another as illustrated in FIG. 7 in which different modules 60, 62, 64 of the invention are connected to each other by means of bus lines 66, 68 extending between the ISA compatible bus pins indicated by reference numerals 70, 72, 74, respectively. 

I claim:
 1. A computer module comprising a central processing unit, a serial port, a parallel port, a drive controller, a keyboard interface, a DRAM interface and flash memory mounted in a relatively flat housing which is adapted to be mounted on a circuit board in a flat position, and a plurality of gull wing connector pins extending from the housing and arranged in a single row along the periphery of the housing for connection to electrical conductors on the circuit board.
 2. The computer module of claim 1 wherein the housing is rectangular.
 3. The computer module of claim 1 wherein the module has a footprint no larger than about 60×80 mm.
 4. The computer module of claim 1 wherein the connector pins correspond in signal type and in number to a standard ISA bus.
 5. A computer module comprising a central processing unit, a serial port, a parallel port, a drive controller, a keyboard interface, a DRAM interface and flash memory mounted in a relatively flat rectangular housing which is adapted to be mounted on a circuit board in a flat position, and a plurality of connector pins extending from the housing and arranged in a single row along three adjacent peripheral edges of the housing for connection to electrical conductors on the circuit board.
 6. The computer module of claim 5 wherein the module has a footprint no larger than about 60×80 mm.
 7. The computer module of claim 5 wherein the connector pins correspond in signal type and in number to a standard ISA bus. 